“In August 2010, researchers from Yale University published a study in the journal Obesity finding that people who took antihistamines regularly were heavier than people who didn't take them at all. The study's authors used data from the Centers for Disease Control and Prevention's (CDC's) National Health and Nutrition Examination Survey 2005-2006 to compare the body weight of 867 adults and their prescription antihistamine use. The two drugs most common in the study were ... Zyrtec, and ... Allegra, and the effect was more pronounced in men. The researchers warned that this was an observational study, and couldn't demonstrate whether antihistamines actually caused the weight gain or if obesity predisposes people to allergies.”
“[I]n a separate study, published in 2009 in the Journal of Clinical Allergy and Immunology ... [u]sing data from the same CDC survey, researchers found that obese children were more likely to suffer from allergies, specifically food allergies, than normal-weight children. "It wasn't clear to us if that really meant that the obesity was the cause of that allergic propensity or not," says Cynthia Visness, PhD, the study's lead author and a research scientist at Rho Inc., the research firm that conducted the study.”
“There isn't much literature available on the link between obesity and allergies, so possible explanations for the associations seen in these two studies are simply theories at this point, Visness says. In her study, she suggested that inflammation could play a role. Fat cells release cytokines, chemicals that promote inflammation, and an allergic reaction triggers inflammation as well.”
Here’s the bumpy part. The title of the Rodale Press article that I have quoted above, asks if allergies can make you fat. The Yale study suggests that the excess weight may be due to allergy medications. Dr. Visness of Rho Inc states that she isn’t sure whether obesity causes allergy, but concludes that obesity might be a contributor to the increased prevalence of allergic disease in children, particularly food allergy, and that systemic inflammation might play a role in the development of allergic disease.
Here is the way I see it; the dominant pathway is allergy leading to inflammation, which leads to excess body fat. From my experience treating overweight and allergic patients in the last 28 years, and from the findings of current medical science, I believe that inflammation is the central issue, with much of that inflammation arising from allergic reactions. Many individuals, including infants and young children have food allergy/reactions, inducing inflammation. Those same individuals often have diets rich in sugar and refined starch; and low in, or devoid of fresh vegetables and fruits, the effect of which additionally induces inflammation in the body. The combination of food allergy/reactions plus a nutrient-poor diet, often result in low energy and a resultant lack of physical exercise, which also increases inflammation. If that weren’t enough, the emotional stress of being overweight can also produce inflammatory chemicals.
One powerful therapy for halting this cycle of inflammation and weight gain is to determine and remove food allergens. In my experience, and in the experience of Mark Hyman, MD, a published expert in health restoration and weight loss, dairy products are one of the most common food allergens that induce weight gain. Taking a week to 2 weeks off of dairy can facilitate weight loss for some. There are those who will not respond quickly and obviously, and they will need the guidance of an experienced healthcare practitioner.